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  <title>Document</title>
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  <script>
    const arr = [1,2,3,4]
    // Array.prototype.removeFirstPosition = function() {
    //   for(let i = 0; i < this.length; i++) {
    //     this[i] = arr[i + 1]
    //   }
    //   return this
    // }
    // console.log(arr.removeFirstPosition())
    // console.log(arr.splice(1,2))
    // const arr = ['e','b','C','d']
    // arr.sort((a,b) => {
    //   return a.toLocaleLowerCase().charCodeAt() - b.toLocaleLowerCase().charCodeAt()
    // })
    // console.log(arr.toString())
  </script>
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